28 EDWARD A. WILSON. 



measurements which are almost identical with those of the King Penguin's egg to measure- 

 ments which are almost half as long and half as wide again. The smallest of the series 

 of fourteen eggs procured by our expedition at Cape Crozier measures 10*7 cm. in length 

 and 8'0 cm. in breadth (see fig. 1., PI. VI.); but there are three eggs which measure 

 less in breadth, one being 7 ' 5 cm. across, and the other two 7 7 cm., though their length 

 is in each case greater, namely, 11 '0 cm., 11 '0 cm., and 12*8 cm. respectively. These 

 figures will give some idea of the variability that exists in the proportionate length 

 and breadth of the eggs, some indeed being long and narrow, and others broad and 

 squat, but all distinctly pyriform. The largest of the series in question measures 

 13 '1 cm. in length, and has a breadth of 8*3 cm. (see fig. 1, PI. VII.), but there is 

 yet another which, though measuring only 12 8 cm. in length, has a breadth of 8 6 cm. 



It is therefore clear that there is a wide range both in actual and in proportionate 

 measurements, even in a limited series of eggs from one breeding colony a fact which 

 may have some bearing upon the age of individuals, if, as I believe to be the case, the 

 younger produce smaller eggs than the older birds. If the age of the laying birds and 

 the size of the eggs they lay increase proportionately, one may argue that where the 

 eggs of a single species vary much in size, there must be a corresponding difference in 

 the age of the individuals ; and so, further, that as some of its eggs are nearly half as 

 big again as others, the Emperor Penguin must be a bird of considerable longevity. 

 This, however, is a supposition which can be made only in the form of a suggestion. 



It is upheld by very few facts, so far as I can ascertain, from the natural difficulty 

 there is in getting a series of eggs from a single bird of any species from year to year. 

 But in the solitary case of a Buzzard (JButeo vulgaris) in which I have seen the eggs 

 laid year by year by the same hen, their size very gradually increased,* and the same 

 observation has been made often enough in the poultry yard with domestic hens. 



Previous to our discovery of the Emperor Penguin's rookery at Cape Crozier in 1902 

 there was but one egg in any known collection which was supposed to be the egg of an 

 Emperor Penguin. This was in the collection of Mr. Walter, of Drayton House, 

 Norwich, and its history, for the details of which I am indebted to him, and to Mr. T. 

 Parkin, of Hastings, is as follows. 



It was brought to Paris from the Antarctic in 1838 by the French South Polar 

 Expedition under Dumont D'Urville. In 1840 or 1841 it was bought in Paris by 

 Dr. (afterwards Sir) Henry Alfred Pitman, who sold his entire collection five years later to 

 the late Mr. H. F. Walter, of Papplewick Hall, Notts. At his death the collection 

 passed into the possession of his son, by whom it was removed to Drayton House, 

 Norwich, where the egg in question now lies. This Drayton egg it has been my 

 privilege, through the courtesy of Mr. Walter, to examine and compare with those 

 from Cape Crozier, and I have no doubt now, even if there had been any real doubt 

 before, that it is the egg of an Emperor Penguin. It measures 10 '9 cm. in length, 



* I have to thank Mr. O. H. Latter, of Charterhouse, for kindly drawing my attention to this series, which is 

 at present in the school museum. 



